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Re: 4.6L Ford MAF was Re: Heat crazed mad scientist



Whoa, whoa, whoa Mike....what are you saying??

What ever happened to the load calculation in the computer? I've read some
of your articles in the past regarding how the computer computes the
engine's load from the mass air meter. By changing the meter's output scale,
you're effectively changing the resulting load calculation. This in turn
would throw off the spark tables. Doesn't this still apply?

Nick

> It's kind of a trick how it works. What you do is scale the voltage
> output of the MAF by tweaking the electronics to sort of 'fool' the ECM
> into thinking it's getting much less massflow into the engine. Then you
> install larger injectors...say the Ford(Bosch) 36#/hr units (dark blue
> tops). What happens is when the engine is running, the ECM 'sees' much
> less voltage from the MAF, so when it does the conversion to massflow,
> it ends up with a much smaller value. The real massflow into the engine
> hasn't changed so the resultant injector pulsewidth (which is now alot
> smaller than stock) works out to give you roughly the correct A/F ratio
> you want. You program the Ford ECM with desired A/F ratio. It figures
> out what the puslewidths need to be to get to your target. Makes things
> REAL easy. But you actually don't need to tweak the ECM at all for any
> of this to work. If the guys who re-calibrate the MAF's do it right,
> they run great out of the box.
>
> Mike....


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